1. Field Of The Invention
This invention relates to rotary internal combustion engines and particularly to such an engine that utilizes autoignition of fuel and water injection into the combustion chamber to increase efficiency, and which also reduces pollution through the injection of water into the combustion chamber.
2. Description Of The Prior Art
The concept of a rotary internal combustion engine is one that presently forms the basis for a great development effort. The reason for such development effort is that it has been found that the rotary internal combustion engine involves mechanical principals that increase the economy of an internal combustion engine. Additionally, because of the relatively fewer number of moving parts in a rotary internal combustion engine, as compared with a conventional reciprocating internal combustion engine, there is less likelihood for wear and consequent breakdowns with attendant expenses. The concept of a rotary engine or motor has of course been incorporated in many different structures.
For instance U.S. Pat. No. 805,162 teaches the concept of a rotary steam engine. U.S. Pat. No. 1,222,475 relates to a rotary internal combustion engine and includes an outer housing cylindrical in configuration and adapted to receive a concentric rotary drive shaft on which is mounted a rotor. On the outer periphery of the rotor are formed combustion chambers in association with each of which is pivotally journaled a piston blade movable between intake, compression, power and exhaust positions by the configuration of the internal periphery of the housing.
U.S. Pat. No. 1,790,256 relates to an internal combustion engine of the rotary type and includes an outer cylindrical housing having an inner periphery divided into four quadrants. Two opposed quadrants are concentric to the central axis of the housing while the remaining two quadrants are elliptical in configuration and cooperate with the circular periphery of the rotor within the housing to effect movement of swing vanes or wings pivotally mounted adjacent the outer periphery of the rotor in association with recesses formed therein. Each of the swing vanes is provided with an aperture or recess in its outer end and cooperates with a valve to trap within such recess a quantity of fuel-air mixture and effect its release at appropriate intervals during which a spark ignites the mixture causing expansion of the products of combustion against the recessed end of the piston, which in turn causes rotary motion of the rotor.
U.S. Pat. No. 1,849,398 is also directed to an internal combustion engine of the rotary type and utilizes an outer housing circular in configuration yet having at 180.degree. opposed positions, pockets which form combustion chambers in cooperation with impact members, each of which includes a compression member movable in relation to the impact member by a generally oval shaped cam. The impact member and compression member are pivotally mounted adjacent the outer periphery of a rotor adapted to be rotated within the inner periphery of the casing as shown.
U.S. Pat. No. 2,915,048 is directed to a hydraulic motor rather than to an internal combustion engine, but is interesting in that even though this is a different type motor, it stills requires the use of an external housing generally cylindrical in configuration and incorporating therewithin a rotatable rotor on the outer periphery of which are mounted a plurality of vanes adapted to swing outwardly in certain positions of the rotor so that the vanes come into sliding contact with the inner periphery of the housing.
U.S. Pat. No. 2,951,469 also relates to a hydraulic type motor rather than an internal combustion engine. This motor utilizes an outer housing having pockets formed in the housing as opposed to being formed in the rotor. Within the housing there is a rotor having pivotally mounted thereon a plurality of vanes which function to displace hydraulic fluid when the casing is rotated in relation to the shaft.
U.S. Pat. No. 3,855,977 provides a cylindrical outer housing having an interior periphery within which is arranged to rotate a rotor having pivotally mounted adjacent its outer periphery a plurality of pistons which are carried in a circular path by the rotor. The pistons are caused to oscillate radially with respect to the housing and the rotor by trunnion pins acting in a cam groove formed in the end plates of the housing. Formed on the outer periphery of each of the pistons is a recess for containing the compressed air-fuel mixture when each of the pistons has been moved into a "compression" position. This internal combustion engine requires 180.degree. rotation for a complete cycle from intake to exhaust, thus providing for two of the pistons to be in a "power mode" at any given time.
From the above it will be seen that while the broad concept of a rotary type engine or motor has been known in the art for sometime, being used variously with steam injection principles and with hydraulic principles and even with internal combustion principles, surprisingly none of these prior art patents combine the concepts of a rotary internal combustion engine with the concepts of fuel injection to provide autoignition because of the pressure and heat cycles generated by the internal combustion engine, nor do any of these prior art patents teach the concept of water injection into such a rotary internal combustion engine capable of autoignition so as to increase the efficiency of such an engine.
With respect to the broad concept of water injection into a conventional internal combustion engine it is noted that this broad concept is known from the prior art. For instance, U.S. Pat. No. 1,966,671 is directed to an internal combustion reciprocating piston engine that teaches the concept of water injection into the combustion chamber of the reciprocating piston engine. U.S. Pat. No. 2,551,073 relates to the specific construction of a water injector for an internal combustion reciprocating piston engine rather than to the combination of a water injection principle in a rotary internal combustion engine. U.S. Pat. No. 2,777,430 is directed to a diesel-type engine that utilizes the concept of separate injection of water and fuel into a combustion chamber. The patent is directed to the concept of separation of the burning fuel from the injected water. Again, the engine in question is a reciprocating type engine.
U.S. Pat. No. 2,789,753 relates to water injection apparatus for a conventional reciprocating type internal combustion engine. Injection of the water is dependent upon the pressure developed by the explosion of the fuel mixture in the combustion chamber. U.S. Pat. No. 3,050,044 teaches the concept of utilizing radiator water as the source of liquid to be injected into the induction system of a conventional reciprocating type internal combustion engine. Similarly, U.S. Pat. No. 3,139,873 teaches the concept of injecting water and exhaust gases into the induction system of a conventional reciprocating type internal combustion engine. U.S. Pat. No. 3,763,832 teaches the concept of injection of water in successive charges into the combustion space in an internal combustion reciprocating type engine as a result of the pressure generated in such space by an explosion.
From the above patents it will be seen that the broad concept of water injection into an internal combustion engine of the "conventional" type is old in the art. It is surprising however that to my knowledge the prior art has not revealed the combination of a rotary internal combustion engine that utilizes both water injection and fuel injection so as to provide autoignition of such fuel mixture.
With the foregoing in mind, it is therefore one of the objects of the present invention to provide a rotary internal combustion engine that utilizes both fuel and water injection, the injection cycle of both being controlled so as to increase the efficiency of the engine.
Another object of the invention is to provide a rotary internal combustion engine of small size in comparison to the horse power rating of the engine.
A still further object of the invention is to provide a rotary internal combustion engine that utilizes relatively few moving parts so as to minimize the possibility of breakdown of such an engine and to facilitate repair thereof.
A still further object of the invention is to provide a two stroke rotary internal combustion engine.
Still another object of the invention is to provide a rotary internal combustion engine of the two stroke type that is capable of high speeds in the area of 2,000 to 3,500 revolutions per minute for extended periods without undue wear upon the engine components.
Rotary internal combustion engines have historically had difficulty with engine seals. Obviously, an effective seal must be made between the rotor and the housing within which the rotor rotates in order for the engine to effectively deliver power as a result of the combination taking place within the combustion chambers. Maintaining the integrity of these seals has been a continuing problem. Accordingly, another object of the present invention is to provide a seal structure and method which includes scavenging combustion cylinder or cavity pressure and applying such pressure behind the seals so that the effectiveness of the seal is controlled by the combustion chamber pressure.
The rotary internal combustion engine has been touted as being one which generates very little vibration. It has been found that the amount of vibration developed by an internal combustion engine, whether it be of the rotary type or the reciprocating type, depends to a large extend on the number of combustion chambers and the number of such combustion chambers that are "fired" in any given revolution of the engine. Accordingly, it is still another object of the present invention to provide a two stroke engine utilizing at least so-called "pistons" operating in association with appropriately configured "combustion chambers," with all six of these pistons being subjected to combustion of a fuel mixture within the associated combustion chamber three times within each revolution of the rotor so as to provide a more balanced engine.
Another problem with regard to rotary internal combustion engines has been the difficulty with which such engines could be scaled up or down to meet the demands of various applications. For instance, so far as is known, rotary internal combustion engines have been used primarily for driving automobiles. Other industries such as the construction industry and the boating industry could utilize the advantages of a rotary internal combustion engine if such engines can be scaled up or down to meet the demands of these particular fields. Accordingly, a still further object of the invention is to provide a rotary internal combustion engine designed to be easily scaled up or down to increase or decrease its horsepower rating.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the embodiment illustrated and described, since It may be embodied in various forms within the scope of the appended claims.